1. Field of the Invention
The present invention generally relates to an image processing apparatus, an imaging apparatus, and an image processing program.
Priority is claimed on Japanese Patent Application No. 2010-057934, filed Mar. 15, 2010, the content of which is incorporated herein by reference.
2. Description of the Related Art
For image forming apparatuses such as digital cameras, an edge emphasizing process is performed for improving sharpness of photographed images. In some cases, the edge emphasizing process causes ringing artifacts around sharpened edges due to undershoot or overshoot effects, degrading the image quality.
To reduce such drawbacks of the edge emphasizing process, Japanese Unexamined Patent Application, First Publication No. 2000-322569 suggested a method that restricts the pixel values of edge emphasized pixels within a range between the maximum and minimum pixel values of non-emphasized neighboring pixels, reducing the ringing artifacts.
However, in some cases, Japanese Unexamined Patent Application, First Publication No. 2000-322569 provides insufficient improvement of the sharpness of images due to over restrictions on the edge emphasizing process.